This invention relates to a device for indexing a worktable which carries a workpiece theron upon which work operations are to be performed. More specifically, the invention relates to a device for linearly moving a worktable in accordance with instructions provided by a programmable device moving with the worktable.
Accurate positioning of a workpiece for machine tool or other work operations, such as drilling or the like, is highly important. Numerous devices for accomplishing the same exist in the prior art but all have inherent deficiencies. For example, in one type of prior art devices the indexing of the worktable is mechanically controlled by a series of cam operated limit switches which, when tripped, stop the worktable until the machine operation is completed. These types of devices are not highly accurate and are susceptible to problems in that there is usually no means provided to lock the worktable in place once positioned. Further, these machines are not readily programmable so that the same machine can perform a variety of work functions. If, for example, a drilling function were being accomplished and it would be desired to vary the drilling pattern, new stops would have to be programmed into the system necessitating the tearing down and repositioning of the various limit switches.
In an effort to improve the accuracy and versatility lacking in the aforementioned device, a number of computer-like devices have been developed to control workpiece positioning. These devices can be, of course, programmable to improve the versatility of the system and can also provide highly accurate positioning, but are often prohibitively expensive and require the services of highly trained personnel to operate and maintain.